Ann: Becoming a substantial holder, page-82

That is quite right.
People think that they can just buy 10's or 100's of millions on the market at competitive price. There is always a limit to what free floating shares are out there. Also it is quite likely that each acquirer, while in the process use his own stock to suppress the unreasonable rise so he gets a best average. They will generally use a broker to handle all this as it is not practical to do on their own. They may give the broker a target price range and leave it to them. If it so happens there are several parties wanting to accumulate, the chase gets hotter. Add to that mix retail holders, retail day traders, it gets quite saucy as we see many a times on screen ourselves.

Any of the above will only push the SP upwards.

Unless & untill some big holders say this is enough for me and start to unload systematically.